Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: entropy



Am I correct that the difference between this disorder you are refering to
and the kind appropriate to entropy is this:
A single pack of cards in a particular sequence can be "disordered",
while to talk about entropy you need an ensemble of sequences.

I'm sure that we both know what entropy is. I'm quite sure that students
know perfectly well what is meant by "ordered" and "disordered" when the
concept is related to a pack of cards. I am not at all sure what you mean
by "the kind appropriate to entropy". Do you have another sort of disorder
in mind appropriate to the context of a pack of cards? My idea and that I
have assumed students have is identical.

I'm not sure I've said that well. What I'm trying to suggest is that
entropy (one kind of disorder) applies when a system is changing between
many microstates. A second kind of disorder is when a system is in a
single, unorganized microstate. Are you are concerned about students
making a distinction between these two kinds of disorder?

As I said, I'm sure we know what entropy is. I'm equally certain that if
we try to relate it to disorder we will not enlighten our students who
have not already learned about entropy the conventional way.

Or is there a third (, fourth...) kind of disorder that I'm missing and
that muddies the waters further?

I don't believe there is even a second kind of disorder worth considering
here. The waters are not at all muddy unless one introduces the concept of
disorder. What is wrong with introducing entropy at an appropriate point
in our students' educational development? No one insists on teaching them
to sum over Feynman diagrams in kindergarten; why tell them fairy stories
about entropy in the twelfth grade? Do they understand how a rainbow is
formed? Spend some time on that one instead.

I'm trying to write up a summary now, but it is not a compelling task.
I feel somehow that I should get back to preparing lectures for tomorrow
instead.

Leigh